SULFONIUM SALT, POLYMER, POLYMER MAKING METHOD, RESIST COMPOSITION, AND PATTERNING PROCESS

摘要

The present invention provides a sulfonium salt represented by general formula (1a). (R^1 represents H, F, CH_3 or CF_3. R^1a through R^1m represent a monovalent hydrocarbon group which can be substituted with a hydrogen atom or a hetero atom or be interposed with a hetero atom. L represents a divalent hydrocarbon group which can be a single bond, be substituted with a hetero atom or be interposed with a hetero atom. X represents a divalent alkylene group in which a part or the whole of hydrogen atoms can be substituted with a fluorine atom. And n represents 0 or 1.) The sulfonium salt having a polymeric anion of the present invention is able to effectively cut an acid labile group among chemical amplification type resist materials, thereby being useful as a monomer for manufacturing a base resin of a radiation sensitive resist material.